In a principal aspect, the present invention relates to an improved solution for cleaning marble surfaces and method for cleaning marble surfaces. Specifically, a stable crystallizing solution containing both magnesium silicofluoride and oxalic acid is disclosed, which can be incorporated into a complete maintenance system has been developed for preserving the appearance of polished marble flooring, terrazzo and limestone. This system covers daily and weekly maintenance along with a periodic maintenance process of crystallization. The performance of the system is quantified by glossmeter readings; that is, an initial pretest reading is compared with a final reading.
Marble is a natural stone often used as a flooring material. It is known for its beauty and permanence. Although commonly considered a very durable material requiring little maintenance, marble is very sensitive to abrasive soils and acid based liquids. Marble is easily scratched by abrasive soils; over time these scratches cause an overall dulling of the polished surface. The result is a marble floor which shows traffic patterns, and looks worn. Thus, various solutions for cleaning marble surfaces and methods for cleaning marble surfaces have been developed to maintain the aesthetically appealing appearance of the marble.
Most commonly, such solutions for cleaning marble surfaces and methods for cleaning marble surfaces comprise a crystallizing agent, that is, a compound that can chemically react with the marble.
A stable solution having both magnesium silicofluoride and oxalic acid is desirable, as solutions having only one of these two cleaning agents will not be sufficiently broad based in their application so as to ensure optimal performance.
A problem thus associated with solutions for cleaning marble surfaces and methods for cleaning marble surfaces that precede the present invention is, that to effect maximum cleaning, they require time-consuming application of two steps to ensure optimal cleaning. Specifically, to obtain a broad based application so as to ensure optimal cleaning, two cleaning solutions would be necessary and, because of the chemistry involved, these would have to be separately applied.
Another problem associated with solutions for cleaning marble surfaces and methods for cleaning marble surfaces that existed before the present invention is that many of them use only one crystallizing agent to restore the gloss on marble and other calcium carbonate containing surfaces.
Still a further problem thus associated with solutions for cleaning marble surfaces and methods for cleaning marble surfaces that precede the present invention is that they can damage or etch the marble if allowed to dry.
This problem is particularly acute where oxalic acid is used as a polishing agent. Historically, oxalic acid has been used to polish marble, as a slurry of this acid can restore the shine of marble. However, in previous applications of oxalic acid, damage to the marble can result if the slurry is permitted to dry.
Still a further problem associated with solutions for cleaning marble surfaces and methods for cleaning marble surfaces that existed before the present invention is that of optimally formulating the cleaning solution to be used.
Thus, a further problem associated with solutions for cleaning marble surfaces and methods for cleaning marble surfaces that existed before the present invention is that of selective performance. For example, magnesium silicofluoride has been used as a crystallizing agent because it reacts with the marble surface. Particularly when used in a buffing process, this acid improves the gloss of marble, hardens the marble, and improves the slip resistance of marble. However, magnesium silicofluoride alone does not permit the greatest breadth of application, as it does not react with all components common to marble and similar floor surfaces.
Yet another problem associated with solutions for cleaning marble surfaces and methods for cleaning marble surfaces that existed before the present invention is that of formulating the chemical to attack the particular impurity. Thus, improper selection of the solution components yields a cleaning solution that is not fully effective in cleaning.
Still a further problem associated with solutions for cleaning marble surfaces and methods for cleaning marble surfaces that existed before the present invention is that of determining the extent of improvement in the marble gloss so as to ensure that proper and effective cleaning has been performed.
Thus, a further problem associated with solutions for cleaning marble surfaces and methods for cleaning marble surfaces that existed before the present invention is that of formulating a combination of compounds that can provide excellent results in restoring and maintaining the gloss of marble while at the same time providing a cost efficient method of application.
Yet a further problem associated with solutions for cleaning marble surfaces and methods for cleaning marble surfaces that existed before the present invention is that they are not energy, time and reagent efficient, and thereby increase the expense and waste of operation.
Still a further problem associated with solutions for cleaning marble surfaces and methods for cleaning marble surfaces that existed before the present invention is that of excessive downtime and lost production caused by cleaning of the floor which results because use of the floor is interrupted.
An even further problem associated with solutions for cleaning marble surfaces and methods for cleaning marble surfaces that existed before the present invention is that of complex system design and expensive manufacture and use of materials.
Thus, various cleaning compounds and systems for cleaning marble and marble-like surfaces have been known for years. Generally, use of magnesium silicofluoride as a cleaning compound is known, as is use of oxalic acid, each of which have been shown to be crystallizing agents. However, the ability to preserve both in solution for extended period of time for use as cleaning solutions for surfaces such as marble, etc. has not been shown.
For example, U.S. Pat. No. 1,574,406, entitled "Composition for Cleaning Stone" and issued to Gustaf A. Nelson on Jun. 12, 1923, generally discloses a cleaning solution for use on granite, stone, marble, tile, etc. comprising ammonium fluoride, oxalic acid and water.
In addition, U.S. Pat. No. 3,150,007, entitled "Process for Cleaning Stone" and issued to Julius M. Kovachy on Sep. 22, 1964, generally discloses a process for cleaning stone utilizing a mixture of ammonium bifluoride, water, gum arabic, sodium bisulfate and barium bisulfate.
U.S. Pat. No. 3,481,879, entitled "Products for Cleaning Stone, Bricks, Concrete and Other Constructional Materials" and issued to Georges Salomone on Dec. 2, 1969, generally discloses a composition for cleaning stone, bricks, concrete and the like comprising water, ammonium bifluoride, barium chloride, magnesium fluosilicate, zinc fluosilicate, hydrofluoric acid and sodium fluosilicate with a stabilizing sugar.
U.S. Pat. No. 4,613,378, entitled "Method of Restoring Marble and Brick Surfaces" and issued to Lawrence Christy on Sep. 23, 1986, generally discloses a marble and brick surface restoring composition having trisodium phosphate, talc and sugar.
U.S. Pat. No. 4,738,876, entitled "Stone Surface Treating Methods and Compositions" and issued to Roger D. George, et al. on Apr. 19, 1988, generally discloses a process for treating stone surfaces such as marble or terrazzo. More particularly, this reference discloses an acid conditioning agent having an acid, such as oxalic acid, a surfactant and an organic solvent.
U.S. Pat. No. 4,756,766, entitled "Method of Cleaning and Conditioning Surfaces" and issued to John H. Thrower on Jul. 12, 1988, generally discloses a process for cleaning and conditioning marble and similar substances using a mixture including zinc sulfate solution and a thickener is used. The mixture cleans both mechanically, through abrasive action, as well as chemically, and prepares the marble for a second cleaning step, which is a solution of water, fluosilicates containing alkaline earth metals or zinc, and a monocarboxylic acid.
U.S. Pat. No. 5,108,514, entitled "In-Situ Method for Cleaning Swimming Pools without Draining the Water" and issued to Kim T. Kisner on Apr. 28, 1992, generally discloses a method for cleaning the interior surfaces of a swimming pool to remove stains, calcium deposits, and the like.
U.S. Pat. No. 5,282,900, entitled "Nonwoven Surface Treating Articles, System Including Same, and Method of Treating Calcium Carbonate-Containing Surfaces with Said System" and issued to James A. McDonell, et al. on Feb. 1, 1994, generally discloses the use of a cleaning pad used in combination with a system for treating calcium carbonate containing surfaces using an acidic crystallizing agent. This reference discloses using either magnesium hexafluorosilicate, oxalic acid, or hydrofluoric acid as a crystallizing agent, but does not teach or suggest a combination of magnesium hexafluorosilicate and oxalic acid.
The present invention constitutes a solution for cleaning marble surfaces and method for cleaning marble surfaces that seeks to overcome the problems discussed above, while at the same time providing a simple, easily manufactured solution and easily performed method that is readily adapted to a variety of applications, including the cleaning of various floor surfaces.